Edge members for ski

ABSTRACT

A ski edge member with: a straight portion divided into a plural number of sections by longitudinally forwardly inclined slit-like cracks, and a web integral with the straight portion and extending horizontally from one side of said straight portion, the web having, in each region corresponding to a crack, a pair of grooves each having one end extending close to the straight portion and the other end being open so as to position the crack midway between the one ends of said pair of grooves. The web further has a connecting member for connecting adjacent ones of said sections flanked, via the pair of grooves, by reinforcing lugs and having an inner cutout at a site substantially on the extension of the crack and having an elongated slot surrounding the inner cutout. The crack is open into the elongated slot, and the connecting member further has a pair of resilient projections defined by the pair of grooves and the elongated slot and also a resilient flap portion defined by said elongated slot and said inner cutout and further having connecting portions connecting said resilient projections with said flap portion. Such an edge member can withstand sufficiently a high applied tensile load without impairing the flexibility of the ski body.

United States Patent [191 Tanahashi 1 Sept. 23, 1975 1 1 EDGE MEMBERSFOR SKI [75] Inventor: Ryoji Tanahashi, Hamamatsu, Japan [73] Assignee:Nippon Gakki Seizo Kabushiki Kaisha, Hamamatsu. Japan 221 Filed: Feb.15,1974

1211 Appl.No.:443,1l5

[30] Foreign Application Priority Data Feb. 20, 1973 Japan 48-20374 [52]U.S. Cl 280/ll.l3 E [51] Int. Cl.- A63C 5/04 [58] Field of Search280/11.13 N, 11.13 P 280/11.l3 E,11.13 .1, 11.13 V, 11.13 Q

[56] References Cited UNITED STATES PATENTS 3,401,949 9/1968 Fouillet280/11.13 N 3,700,252 10/1972 Schultes 280/1 1.13 N 3,751,054 8/1973Deutsch 280/11.13 E

FOREIGN PATENTS OR APPLlCATIONS 1,475,632 2/1967 France 280/1 1.13 N464,035 1l/1968 Switzerland 280/11.13 E

Primary ExaminerDavid Schonberg Assistant Examiner-Milton L. SmithAttorney, Agent, or Firm-Cushman, Darby 84 Cushman [5 7] ABSTRACT A skiedge member with: a straight portion divided into a plural number ofsections by longitudinally forwardly inclined slit-like cracks. and aweb integral with the straight portion and extending horizontally fromone side of said straight portion. the web having. in each regioncorresponding to a crack, a pair of grooves eachhaving one end extendingclose to the straight portion and the other end being open so as toposition the crack midway between the one ends of said pair of grooves.The web further has a connecting member for connecting adjacent ones ofsaid sections flanked, via the pair of grooves, by reinforcing lugs andhaving an inner cutout at a site substantially on the extension of thecrack and having an elongated slot surrounding the inner cutout. Thecrack is open into the elongated slot, and the connecting member furtherhas a pair of resilient projections defined by the pair of grooves andthe elongated slot and also a resilient flap. portion defined by saidelongated slot and said inner cutout and further having connectingportions connecting said resilient projections with said flap portion.Such an edge member can withstand sufficiently a high applied tensileload without impairing the flexibility of the ski body.

4 Claims, 7 Drawing Figures US Patent Sept. 23,1975 Sheet 10f2 3,907,314

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EDGE MEMBERS FOR SKI BACKGROUND OF THE INVENTION 1. Field of theInvention:

The present invention pertains to edge members for skis, and moreparticularly it relates to edge members for skis such that they do notimpair the flexibility of ski bodies.

2. Description of the Prior Art:

A ski is generally comprised of a ski body and a shoefastening meansattached to the ski body. The ski body is provided, longitudinally ofthe ski body, with edge members made in general of steel for the purposeof protecting the sole surface and for the purpose of easily causing thelower lateral edge portion of the sole to bite into the snow surface,which is the so-called edging performance, when it is intended to reducethe speed during gliding. However, the ski body per se is not rigid butresilient, rich in flexibility. In order to maintain this resiliency.there have been many efforts in the arrangement and design of the skibody. How.- ever, when edge members made of rigid steel are fixed tothesole surface of a ski body, the initial resiliency of the ski body isimpaired, and the ski body equipped with such rigid edge members willitself have an additional rigidity. Thus, the desired characteristics ofthe resulting complete ski which has been produced with great designingskill will be lost.

However, most skis cannot do without edge members. For this reason,there are many great efforts in the development of improved edge memberswhich will not reduce the resiliency of the ski body. Recently, therehave been introduced edge members called cracked edge members" eachhaving a plurality of spaced slits in thestraight running portion toprovide a plural number of straight sections. As compared with the prioredge members each having a continuous straight portion, the cracked edgemembers are constructed so as not to substantially impair theflexibility of the ski body.

As the cracked edge members which are either available now or known atpresent, there may be given the following two types, one of which is thecracked edge member described in Japanese Pat. Publication No. 45-6341and the other is the cracked edge member disclosed in West GermanUtility Model No. 6905035 representing an improvement of the former. Theformer, however, has the problem that the edge member is susceptible tobreakage as the bending stress applied to the edge member isconcentrated in the portions having cracks. The cracks have no advantageother than that they do not impair the flexibility of the ski body. Itmay be said that the cracks themselves even contribute to making theedge member break more easily whenever a substantial tensile stress isapplied to the cracked portions. Therefore, efforts have been made towill be subjected to a marked pulling force. If, therefore, the edgemembers are unable to adapt themselves to this stress applied, they willeventually break. However, in case this easily breakable portion of theedge member is reinforcedwith a rigid element, then the edge memberhaving such a reinforced portion will no doubt possess an excessivelygreat strength against the tensile stress applied, contributing to anincrease in the rigidity of the edge member. However, the flexibility orresiliency of the ski body will be reduced greatly.

The aforesaid latter steel edge members disclosed in the West GermanUtility Model have been proposed as an improvement of the known edgemembers described above. However, the edge members of this West GermanUtility Model are too excessively resistant to the tensile stressesapplied so thatthey will not break even when stressesare concentratedthereto and they have an enhanced durability. These edge members,however, sacrifice the flexibility of the ski body.

In case a tensile load is applied to edge members because a pers'onmounts on skis, the archbend regions of these skiswill be subjected to abending load. Accordingly, the sole surface of each ski which is locatedat a position lower than the center of the ski body will have to supportthe tensile load applied. The ski body as a whole also will undergo anextension to a slight degree. Each edge member which is integrallyattached to the ski body will be caused to extend also. However, in casethe edge members employed are cracked edge members,such an extensionwill be manifested as the total of both the extension strainrepresenting the widening apart of the respective slit-like cracks ofthe edge member andthe extension strain of the straight portions of theedge member which are the portions that unite together the respectivesections divided by the cracks. An edge member itself requires only asufficient rigidity. In the event, however, that the ski body is causedto extend itself by the bending load applied, it will be noted that,unless the edge members which are arranged as integral parts of the skibody adapt themselves so as toex ert an extension in conformity to theextension of the skibody, there will naturally develop staggering ofpositions between the edge members and the ski body. Development of suchstaggering in position of these parts-of a ski, in turn, will veryundesirably result in either the detachment of the edge members from theskibody or the impairment of the flexibility of the ski body. Thus, ifthe edge members are made of a material, s uc h as rubber, which canextend in confor mity with the extension of the ski body, there willdevelop no staggering in position between the edge members and the skibody nor will there arise any impairment of the flexibility of the skibody. However, in reality it is impossible to find a material whichmeets the aforesaid requirements as edge members of a ski,

In order to solve the aforesaid problems where the material-of edgemembers is limited at present to steel, there must be developed a deviceto provide edge members having a somewhat lessened rigidity. If thestraight portion of a steel edge member is provided with a number. ofclosely positioned cracks throughout its length, such an edge memberwould surely possess a great adaptability to the deformations developedby the ski body. However, such a cracked edge member will member willnever be suitable for use.

It is the aforesaid known edge member that has been designed with theaim of imparting thereto both an adaptability to the ski body and adesirable strength under the restriction in term of material that theedge member has to be made of steel. In such a known edge member. itwould be ideal if this edge member functions in such a way that.whenever the edge member is caused to extend owing to the tensile stressapplied to its entire length. the gaps of the slit-like cracks willbecome widened apart. causing the edge member to exert an extension,without any resistance. in conformity with the extension of the skibody. However. in reality the straight portions which serve to connectthe divided sections together possess a rigidity and impair theflexibility of the ski body.

SUMMARY OF THE INVENTION It is, therefore, a primary object of thepresent invention to provide an edge member made of steel. which is muchcloser to an ideal edge member as compared with the aforesaid two typesof edge members of the prior art.

Another object of the present invention is to provide a cracked edgemember of the type described, which is not too rigid as would decreasethe operability in attaching it to a ski body nor so rigid as wouldhamper the bending deformation of the ski body but can sufficiently copewith the widening of the gaps of the cracks whenever a substantialtensile stress is applied thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a partof an L-shaped edge member embodying an example of the presentinvention.

FIG. 2 is a bottom plan view of the same part of FIG. 1.

FIG. 3 is a perspective view of a part of the same edge member of FIG. 1but shows the repetition of the patern of the connecting members andreinforcing lugs both of which form a part of the edge member of FIG. 1.

FIG. 4 is a bottom plan view similar to FIG. 2, showing a modifiedexample of the essential part of the edge member according to thepresent invention.

FIG. 5 is a similar view, showing still another modified example.

FIG. 6 is a cross section ofa ski to show how the edge members of thepresent invention are attached to the ski.

FIG. 7 is a diagrammatic fragmentary side view of a part of the straightportion of an edge member according to the present invention to show aninclined slitlike crack.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention willhereunder be described on some preferred embodiments by referring to theaccompanying drawings which are given only by way of example.

By referring to FIGS. 1 through 3, there is shown a part of a firstexample of the L-shaped cracked edge member according to the presentinvention. This edge member shown generally at A is made of steel and isto be provided on a ski body in the longitudinal direction thereof. Thestraight portion of the edge member A which is indicated generally at lis of a substantially square cross section. A web 2 having its uppersurface positioned at the same plane with that of the upper surface ofthe straight portion 1 and having a thickness which is about one thirdof the vertical height of the straight portion 1 extends horizontallyfrom a lateral side of the straight portion 1 for the entire lengththereof.

This straight portion I is provided with slit-like cracks 11 which aredisposed at constant intervals. Each of these cracks 11 is inclined insuch a way that its upper portion is positioned closer toward the shovelportion of the ski and its bottom portion is positioned closer towardthe tail of the ski relative to the running direction X of the ski, asshown in FIG. 7. Depending on the type of ski and on the material withwhich the edge member is made, the intervals between the cracks 11 arein the range of, generally, 2 to 3 cm.

The web 2 has a plural number of connecting members indicated generallyat 21 and reinforcing lugs generally indicated at 22. This connectingmember 21 has an elongated slot 21:: which is of a substantiallysemicircular arcuatc configuration having its center C located on theextension I- of the slit-like crack 11. The crack 11 is extended towardthe center C so that the crack is open into the slot 210. That portionof the connecting member 21 containing the center C is provided in thefrom of a substantially Ushaped inner cutout 2112 of a substantial widthin the radial direction of the aforesaid arcuate slot 21a and havingsubstantially parallel legs of U-shape and having a rounded closedbottom of said U-shape so that the end edge of the connecting member 21in the portion which is away from the straight portion 1 is open.Between the connecting member 21 and a reinforcing lug 22. there isprovided a groove 23 which is arcuate in configuration concentric withthe semi-circular elongated slot 21a. This arcuate groove 23 extends atits one end toward the inner side of the straight portion 1 in such away that this one end terminates as a closed end with a small intervalfrom said inner side of the straight portion 1. In addition, this closedend of the arcuate groove 23 which is located on the straight portion 1side is positioned closer to the slit-like crack 11 which is formed inthe straight portion 1.

The reinforcing lug 22 is formed between two arcu ate grooves 23 and 23.This reinforcing lug 22 is provided. at a central portion. with anopening 221! for the purpose of enhancing the adhcrency of the edgemember A to the component members of the ski body by allowing anadhesive to be applied in this opening 221! to be filled therein. Thisreinforcing lug 22 has flexibility because of its opening 22a.

Within each pitch between the adjacent slit-like cracks l1 and 11 isdisposed one connecting member 21 and one reinforcing lug 22,respectively. The connecting member 21 is such that it is locally cutaway at the semicircular elongated slot 21a and at the inner cutout2112. This inner cutout 21/: has a closed end edge 21']; which is roundin configuration and concentric with the semi-circular elongated slot21a. The ends of this round closed end edge 21 '12 have extensions 21")and 21"]; which are rectilinear and form parallel legs of U-shape havingan open other end. The connecting member 21 corresponding to a crack 1 lis rendered as a continuous member longitudinally of the edge member Aby a solid part or flap 21A which is semi-circular and flexible andlocated on the proximal center side of the semi-circular elongated slot21a. This semi-circular flap 21A is not of a wave-like shape. Theproximal edge is shaped to have a round edge by the aforesaid innercutout 21b having a considerable depth. Along therewith, thissemi-circular flap 21A gives a basis for the general contour of theconnecting member 21. Moreover, the outer peripheral solid portion orprojection 21B of the semi-circular elongated slot 21a has a breadthsimilar to that of the semi-circular flap 21A and an arcuate shape whichis substantially concentric with this semi-circular flap 21A. Thus. thisportion 218 is provided as a flexible element. One end of the outerperipheral solid portion or projection 21B joins the straight portion 1of the edge member A. The arcuate groove 23 in this example is notperpendicular to the length of the edge member 1 nor is it of awave-like shape as will be clear from the foregoing statement.

This arcuate groove 23 is provided so as to extend, in

the form of a substantially concentric arc with respect to the arcuateslot 21a until it terminates shortly before joining the straight portion1, thus rendering both the reinforcing lug 22 and the connecting member21 independent of each other.

Next. description will be made on the actual deformation which the skishaving the aforesaid edge members will undergo when mounted by a user.

In case these skis are not mounted by a person, each ski retains itsinitial so-called arch-bend," i.e. the form of the central part of theski which is warped in an archlike bent form. Whenever a substantialbending load is applied to the ski from thereabove, this arch-bendbecomes depressed or sunken a little, causing a tensile stress todevelop at the surface of sole. Corresponding to this tensile stress,the edge members of the ski also will be subjected to a tensile load.

In such a case, the gaps of the respective slit-like cracks of each edgemember will become widened apart and accordingly the edge member willdevelop an extension corresponding to the tensile stress appliedthereto. The widening of the gap of crack 11 will bring an effect in theweb 2 such that the semi-circular flap 21A of the connecting member 21will extend longitudinally of the edge member A and this edge member asa whole will accordingly develop an extension due to the tensile loadapplied. This tensile load. when applied to the edge member, issupported by the semi-circular flap 21A and the outer peripheral solidportion or projection 218, in such a manner that one half of this loadis borne by one ofthese two elements 21A and 21B. respectively. As aresult, this edge member A is able to withstand a load which is twice asgreat as the load which could be borne by a conventional edge member.

- In other words. the degree of extension which can be exerted by theconnecting member 21 is extremely great as compared with that exerted bythe straight portion 1 of the edge member. Even in case the gap of thecrack is widened substantially, the connecting member 21 is able todevelop a lengthwise extension to sufficiently cope with this wideningof the crack. This absorption of extension by the connecting member 21is materialized by the fact that this connecting member 21 whichconnects those divided sections of the straight portion 1 of the edgemember A which are rendered to severed state by the provision of cracksis of such a configuration as giving a great allowance for an extensionby the cooperation of the semi-circular elongated slot 21a surroundingthe semi-circular flap 21A and the inner cutout 2112 provided in aradial direction of the elongated slot 210. Especially, the connectingmember 21 which faces the crack 1 l is of a configuration whose solidregions each has a small breadth. and also thearcuategrooves 23 and 23which are provided on the outer sides of the connecting member 21 areeach of such an arcuate configuration extending at one ends toward theslit-like crack 11. Accordingly. when compared with known cracked edgemembers. it is possible to expect markedly great elasticity from theedge members of this example of the present invention.

FIG. 4shows another embodiment which shows a modification of especiallythe configurations of the connecting member 221 and of its surroundinggrooves 223. In this example, the connecting member 221 generally has asomewhat rectangular configuration. More specifically, the connectingmember 221 has an elongated slot 221a which is of a substantiallyU-shaped configuration in which both legs of U-shape are substantiallysymmetrical relative to the extension of the slit-like crack 11. Thatportion of the connecting member 221 corresponding to the inner cutout21b of FIG. 2 is provided as an inner cutout 2211) having asubstantially U-shaped configuration but having a rather flat closedbottom 221'!) of U-shape. Therefore, the solid part 221A is ofagenerally U-shaped configuration having a rather flat bottom of U-shape.Moreover, the outer peripheral projection 21B of FIG. 2 is provided, inthis example of FIG. 4, in the form of generally a straight projectionas shown at 2218. The arcuate groove 23 of FIG. 1 is provided, in thisexample of FIG. 4, in the form of a generally straight U-shape groove;223 having a generally flat bottom of U-shape having substantiallyparallel legs of U-shape. Both of these elements 221A and 2218 areresilient as in the preceding first example. The reinforcing lug 222having an opening 222a is substantially similar to the flexiblereinforcing lug 22 of FIGS. 1 and 2 excepting for the substantiallystraight edge line adjacent to the groove 223. The flexible outerperipheral projection 2218 and the flap 221A which is contiguous to theprojection 221B jointly cooperate in withstanding a deformation stressapplied to the edge member A having these elements 221B and 221A.

FIG. 5 shows a still another embodiment. In this embodiment, theconnecting member 321 has a generally one longitudinal half of an ovalshape. This connecting member 321 has an elongated slot 321a which is ofan oblong configuration defined between two lines each beingsubstantially one half of an oval shape, and this slot 321:! issubstantially symmetrical relative to the slit-like crack 11. The innercutout 21b of FIG. 2 is provided. in this example of FIG. 5, as an innercutout 321!) having a configuration which is a substantially onelongitudinal half of an oval shape with its apex which is closer to thestraight portion 1 being rounded and with its opening being widenedbecause of the curved extensions 321 b of edges of the leg portions of awide U-shape inner cutout 3211;. Therefore, the flexible flap 321A is ofa substantially one longitudinal half of an oval shape. The groove 323is of a configuration as shown in FIG. 5. forming an elongated flexibleprojection 3218 as shown. The flap 321A is contiguous with theprojection 3218 and they cooperatively resist any deformation stressapplied to the edge member A In each of the respective embodiments ofFIGS. 4 and 5, the patterns of the connecting member and the adjacentreinforcing lug are to occur repeatedly in the same manner as shown inFIG. 3 which represents the first example.

In each of the last two examples. the cracks 11 are open into theelongated slot 221:! or 32141 and are each provided so as to beinclinedwith its upper end closer to the shovel portion of the ski in the samemanner as described in connection with the first example.

As shown in FIG. 6, the edge members A according to the presentinvention are provided on both sides of the ski body. Reference numeral24 represents the top surface member of a ski. 25. core members. 26.side members. and 27. the bottom or sole member of the ski. The edgemembers A of this invention are fixedly secured between the bottom andcore members. Top edge members 28 may be provided at the upper parts ofthe ski.

As has been stated. according to the present invention. a ski isprovided with an appropriate number of slit-like cracks. Because ofthese cracks. the edge members are not of such a rigidity as woulddecrease the sound efficiency of attaching them to the ski body or wouldhamper the bending deformation of the ski body. Besides, the edge memberas a whole can sufficiently accomodate the widening of the crackswhenever a tensile load is applied to the edge member. Thus. an idealedge member is obtained.

1 claim:

1. An edge member for a ski. comprising a straight portion and a webextending horizontally from one side of said straight portion.

said straight portion being divided into a plural number of sections byslit-like cracks.

said web having. in each region corresponding to a crack. a pair ofgrooves each having one closed end located close to the straight portionand an open other end. said pair of grooves being positioned so that thecrack is intermediate the closed ends of said pair of grooves.

said web further having. in each said region. a connecting member forconnecting adjacent ones of said sections of the straight portion. saidconnecting member being flanked. via said pair of grooves and. byreinforcing members. said reinforcing members forming the portion of theweb between successive pairs of grooves.

said connecting member further having. at a site substantiallycorresponding to the extension of said crack. an inner cutout with oneclosed end and open other end and an elongated slot surrounding thisinner cutout. said crack being open into the elongated slot.

said connecting member further having a pair of resilient projectionsdefined by said pair of grooves and said elongated slot; a resilientflap defined by said elongated slot andsaid inner cutout; and connectingportions for connecting said resilient projections with said flap.

2. An edge member according to claim 1, in which said elongated slot issubstantially semi-circular in configuration. and said closed one end ofthe inner cutout has a round bottom edge concentric with saidsemicircular elongated slot. and said pair of grooves are eachsubstantially concentric with said semi-circular elongated slot.

3. An edge member according to claim 1, in which said elongated slot issubstantially U-shape in configuration with the legs of U-shape beingsubstantially parallel with each other. and said inner cutout issubstantially U-shape with its legs of U-shape extending substantiallyparallel with the legs of said elongated slot and its closed bottom hasa substantially flat edge. and said a pair of grooves each has asubstantially U-shape with its closed bottom having a substantially flatedge and its legs of U-shape extending substantially parallel with thelegs of said elongated slot. the entire connecting member thus having agenerally rectangular configuration.

4. An edge member according to claim 1. in which said elongated slot isof a configuration substantially one longitudinal half of an oval shape.and said inner cutout is of a configuration substantially onelongitudinal half of an oval shape. and said a pair of grooves each hasa configuration for defining the curved outer peripheral part orprojection of the elongated slot.

1. An edge member for a ski, comprising a straight portion and a webextending horizontally from one side of said straight portion, saidstraight portion being divided into a plural number of sections byslit-like cracks, said web having, in each region corresponding to acrack, a pair of grooves each having one closed end located close to thestraight portion and an open other end, said pair of grooves beingpositioned so that the crack is intermediate the closed ends of saidpair of grooves, said web further having, in each said region, aconnecting member for connecting adjacent ones of said sections of thestraight portion, said connecting member being flanked, via said pair ofgrooves and, by reinforcing members, said reinforcing members formingthe portion of the web between successive pairs of grooves, saidconnecting member further having, at a site substantially correspondingto the extension of said crack, an inner cutout with one closed end andopen other end and an elongated slot surrounding this inner cutout, saidcrack being open into the elongated slot, said connecting member furtherhaving a pair of resilient projections defined by said pair of groovesand said elongated slot; a resilient flap defined by said elongated slotand said inner cutout; and connecting portions for connecting saidresilient projections with said flap.
 2. An edge member according toclaim 1, in which said elongated slot is substantially semi-circular inconfiguration, and said closed one end of the inner cutout has a roundbottom edge concentric with said semi-circular elongated slot, and saidpair of grooves are each substantially concentric with saidsemi-circular elongated slot.
 3. An edge member according to claim 1, inwhich said elongated slot is substantially U-shape in configuration withthe legs of U-shape being substantially parallel with each other, andsaid inner cutout is substantially U-shape with its legs of U-shapeextending substantially parallel with the legs of said elongated slotand its closed bottom has a substantially flat edge, and said a pair ofgrooves each has a substantially U-shape with its closed bottom having asubstantially flat edge and its legs of U-shape extending substantiallyparallel with the legs of said elongated slot, the entire connectingmember thus having a generally rectangular configuration.
 4. An edgemember according to claim 1, in which said elongated slot is of aconfiguration substantially one longitudinal half of an oval shape, andsaid inner cutout is of a configuration substantially one longitudinalhalf of an oval shape, and said a pair of grooves each has aconfiguration for defining the curved outer peripheral part orprojection of the elongated slot.